I can't use private key, it keeps asking me passphrase

If you keep getting following messages:

Enter the passphrase for private key “id_rsa"

It could be your private key is encrypted, to confirm this you can open your key file in any text editor, first three lines should like these:

-----BEGIN DSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: DES-EDE3-CBC,AF79F9904FBFC4E0

If "Proc-Type" field contains "ENCRYPTED", then this private key is encrypted. You may have question -- why ssh command line never ask me for passphrase when I execute it in Terminal.app?

It could be you have added this private key to ssh-agent, so it is the ssh-agent actually “typing” the passphrase on you behalf.

Fortunately, you can get your passphrase back from "Keychain Access”:

  1. Open "Keychain Access” app
  2. In the top right search box, type in “SSH:” to search your passphrases
  3. Item that contains passphrase of the private key should listed on search results

If you are sure your private key is unencrypted, or the found passphrase is not work, please contact us to get support.